nfsd: decode implementation id

Decode the implementation ID and display in nfsd/clients/#/info.  It may
be help identify the client.  It won't be used otherwise.

(When this went into the protocol, I thought the implementation ID would
be a slippery slope towards implementation-specific workarounds as with
the http user-agent.  But I guess I was wrong, the risk seems pretty low
now.)

Signed-off-by: J. Bruce Fields <bfields@redhat.com>

4 files changed, 46 insertions, 12 deletions

diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 640cd221fc77..94de5c348a41 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -1899,6 +1899,8 @@ static void __free_client(struct kref *k)
         free_svc_cred(&clp->cl_cred);
         kfree(clp->cl_ownerstr_hashtbl);
         kfree(clp->cl_name.data);
+        kfree(clp->cl_nii_domain.data);
+        kfree(clp->cl_nii_name.data);
         idr_destroy(&clp->cl_stateids);
         kmem_cache_free(client_slab, clp);
 }
@@ -2261,6 +2263,15 @@ static int client_info_show(struct seq_file *m, void *v)
         seq_printf(m, "name: ");
         seq_quote_mem(m, clp->cl_name.data, clp->cl_name.len);
         seq_printf(m, "\nminor version: %d\n", clp->cl_minorversion);
+        if (clp->cl_nii_domain.data) {
+                seq_printf(m, "Implementation domain: ");
+                seq_quote_mem(m, clp->cl_nii_domain.data,
+                                        clp->cl_nii_domain.len);
+                seq_printf(m, "\nImplementation name: ");
+                seq_quote_mem(m, clp->cl_nii_name.data, clp->cl_nii_name.len);
+                seq_printf(m, "\nImplementation time: [%ld, %ld]\n",
+                        clp->cl_nii_time.tv_sec, clp->cl_nii_time.tv_nsec);
+        }
         drop_client(clp);
 
         return 0;
@@ -2901,6 +2912,22 @@ static bool client_has_state(struct nfs4_client *clp)
                 || !list_empty(&clp->async_copies);
 }
 
+static __be32 copy_impl_id(struct nfs4_client *clp,
+                                struct nfsd4_exchange_id *exid)
+{
+        if (!exid->nii_domain.data)
+                return 0;
+        xdr_netobj_dup(&clp->cl_nii_domain, &exid->nii_domain, GFP_KERNEL);
+        if (!clp->cl_nii_domain.data)
+                return nfserr_jukebox;
+        xdr_netobj_dup(&clp->cl_nii_name, &exid->nii_name, GFP_KERNEL);
+        if (!clp->cl_nii_name.data)
+                return nfserr_jukebox;
+        clp->cl_nii_time.tv_sec = exid->nii_time.tv_sec;
+        clp->cl_nii_time.tv_nsec = exid->nii_time.tv_nsec;
+        return 0;
+}
+
 __be32
 nfsd4_exchange_id(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
                 union nfsd4_op_u *u)
@@ -2927,6 +2954,9 @@ nfsd4_exchange_id(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
         new = create_client(exid->clname, rqstp, &verf);
         if (new == NULL)
                 return nfserr_jukebox;
+        status = copy_impl_id(new, exid);
+        if (status)
+                goto out_nolock;
 
         switch (exid->spa_how) {
         case SP4_MACH_CRED:
diff --git a/fs/nfsd/nfs4xdr.c b/fs/nfsd/nfs4xdr.c
index 548a5a843b67..442811809f3d 100644
--- a/fs/nfsd/nfs4xdr.c
+++ b/fs/nfsd/nfs4xdr.c
@@ -1389,7 +1389,6 @@ nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
                 goto xdr_error;
         }
 
-        /* Ignore Implementation ID */
         READ_BUF(4);    /* nfs_impl_id4 array length */
         dummy = be32_to_cpup(p++);
 
@@ -1397,21 +1396,19 @@ nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
                 goto xdr_error;
 
         if (dummy == 1) {
-                /* nii_domain */
-                READ_BUF(4);
-                dummy = be32_to_cpup(p++);
-                READ_BUF(dummy);
-                p += XDR_QUADLEN(dummy);
+                status = nfsd4_decode_opaque(argp, &exid->nii_domain);
+                if (status)
+                        goto xdr_error;
 
                 /* nii_name */
-                READ_BUF(4);
-                dummy = be32_to_cpup(p++);
-                READ_BUF(dummy);
-                p += XDR_QUADLEN(dummy);
+                status = nfsd4_decode_opaque(argp, &exid->nii_name);
+                if (status)
+                        goto xdr_error;
 
                 /* nii_date */
-                READ_BUF(12);
-                p += 3;
+                status = nfsd4_decode_time(argp, &exid->nii_time);
+                if (status)
+                        goto xdr_error;
         }
         DECODE_TAIL;
 }
diff --git a/fs/nfsd/state.h b/fs/nfsd/state.h
index 81852cbf6b0a..8cb20cab012b 100644
--- a/fs/nfsd/state.h
+++ b/fs/nfsd/state.h
@@ -317,6 +317,10 @@ struct nfs4_client {
         clientid_t              cl_clientid;    /* generated by server */
         nfs4_verifier           cl_confirm;     /* generated by server */
         u32                     cl_minorversion;
+        /* NFSv4.1 client implementation id: */
+        struct xdr_netobj       cl_nii_domain;
+        struct xdr_netobj       cl_nii_name;
+        struct timespec         cl_nii_time;
 
         /* for v4.0 and v4.1 callbacks: */
         struct nfs4_cb_conn     cl_cb_conn;
diff --git a/fs/nfsd/xdr4.h b/fs/nfsd/xdr4.h
index c2b631eefc6d..d64c870f998a 100644
--- a/fs/nfsd/xdr4.h
+++ b/fs/nfsd/xdr4.h
@@ -410,6 +410,9 @@ struct nfsd4_exchange_id {
         int             spa_how;
         u32             spo_must_enforce[3];
         u32             spo_must_allow[3];
+        struct xdr_netobj nii_domain;
+        struct xdr_netobj nii_name;
+        struct timespec64 nii_time;
 };
 
 struct nfsd4_sequence {